JPS6135988A - Material to be recorded - Google Patents

Abstract

PURPOSE:To enhance ink receptivity and image sharpness, in a material to be recorded for ink jet recording having an ink holding layer and an ink pervious layer, by making the ink holding capacity of the ink holding layer larger than that of the pervious layer. CONSTITUTION:An ink holding layer comprising a hydrophilic material, for example, albumin, gelatine or starch is provided on a substrate with a thickness of about 10-200mum such as paper, cloth or a resin film in a thickness of about 0.5-30mum and an ink pervious layer with a thickness of about 10mum, pref., about 0.1-5mum is formed on said ink holding layer from a polymer of which the hydrophilicity is equal or inferior to that of the polymer of the ink holding layer. As the polymer of the ink pervious layer, a vinyl polymer, vinylon or polyurethane are designated and the ink holding capacity per a unit area of the formed ink pervious layer is set so as to be made equal to or lower than that of the ink holding layer.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a recording material suitably used in an inkjet recording method, and in particular has excellent ink receptivity and clarity of a recorded image, and When the material is a translucent recording material, it relates to a recording material that has excellent ink receptivity and translucency.

(Prior Art) The inkjet recording method uses various ink (recording liquid) ejection methods, such as an electrostatic suction method, a method that applies mechanical vibration or displacement to the recording liquid using a piezoelectric element, and a method that applies mechanical vibration or displacement to the recording liquid using a piezoelectric element. In this method, small droplets of ink are generated and made to fly by foaming and using the pressure of the foam, and some or all of these droplets adhere to a recording material such as paper to perform recording, but this method generates noise. It is attracting attention as a recording method that allows for high-speed printing and multicolor printing.

Inks for inkjet recording are mainly water-based in terms of safety and recording properties.
Polyhydric alcohols and the like are often added to prevent nozzle clogging and improve ejection characteristics.

The recording material used in this inkjet recording method has conventionally been a recording material made of a base material called ordinary paper or inkjet recording paper provided with a porous ink absorbing layer. However, as the performance of inkjet recording apparatuses improves and becomes more widespread, such as higher recording speeds and multicolor recording, more sophisticated and wide-ranging properties are being required of recording materials. In other words, in order to obtain high-resolution, high-quality recorded images, the recording material for inkjet recording must (1) be able to fix the ink to the recording material as quickly as possible, and (2) have overlapping ink dots. (3) Even if the ink droplets deposited later do not flow into the dots deposited earlier, (3) Although the ink droplets will spread to some extent on the recording material,
(4) The shape of the ink dot should be close to a perfect circle and its circumference should be smooth. (5) The OD of the ink dot should be the same. It is necessary to satisfy basic requirements such as high optical density (optical density) and no blurring around the dots.

Furthermore, in order to obtain high-resolution recorded image quality comparable to color photography using multicolor inkjet recording, in addition to the above-mentioned required performance, (6) the coloring components of the ink must have excellent color development; 7) The ink fixation properties are particularly excellent, as the same number of droplets as the number of ink colors may adhere to the same spot, (8) The surface must be glossy, (9) Whiteness A high level of performance, etc., is required.

In addition, images recorded by inkjet recording have traditionally been used exclusively for surface image observation, but as the performance of inkjet recording devices has improved and become more widespread, recording materials suitable for purposes other than surface image observation have become available. It is becoming demanded. Applications of recording materials other than surface image observation include those used to project recorded images onto a screen, etc. using an optical device such as a slide or 0HP (overhead projector), and observe those images4. Examples include color separation plates used to create positive plates for color printing, and CMF (color mosaic filters) used in color displays such as liquid crystals.

When a recording material is used for surface image observation, the diffused light of the recorded image is mainly observed, whereas for recording materials used in these applications, the problem is mainly the transmitted light of the recorded image. Become. Therefore, it is required to have excellent light transmittance, especially linear light transmittance, in addition to the above-mentioned performance requirements of the general recording material for inkjet recording.

(The problem that the invention is trying to solve) However,
The reality is that there is still no known recording material that satisfies all of these required performances.

Furthermore, most conventional recording materials for surface image observation use a method in which a porous ink absorbing layer is provided on the surface, and a recording liquid is absorbed into the porous voids to fix the recording agent.

On the other hand, when the surface of the ink absorption layer is non-porous, non-volatile components such as polyhydric alcohols in the ink remain on the surface of the recording material for a long time after recording, and the drying and fixing time of the ink is long. However, there are disadvantages in that clothing may get dirty or the recorded image may be damaged if it comes into contact with the recorded image.

An object of the present invention is to provide a recording material for inkjet recording that is particularly excellent in ink receptivity and the clarity of recorded images.

Still another object of the present invention is to use an optical device such as a slide or an OHP to project a recorded image onto a screen for observation, a color separation plate when creating a positive plate for color printing, or a liquid crystal display. An object of the present invention is to provide a translucent recording material for inkjet recording that can be used for observation of transmitted light such as CMF used in color displays.

The above and other objects of the invention are achieved by the following invention.

(Disclosure of the Invention) That is, in a recording material having an ink retaining layer and an ink permeable layer, the ink retaining capacity per unit area of the ink retaining layer is equal to the ink retaining capacity per unit area of the ink transmitting layer. This is a recording material characterized by the above.

To explain the present invention in detail, the recording material of the present invention has an ink containing an ink having a specific property on its ink retaining layer and having an ink retaining capacity less than or equal to the ink retaining capacity per unit area of the ink retaining layer. The main feature is that a transparent layer is provided, and the object of the present invention is mainly achieved thereby.

The recording material of the present invention generally comprises a base material as a support, an ink retaining layer provided on the surface of the base material, and an ink permeable layer provided on the ink retaining layer, for example, as a particularly preferred main embodiment.

(1) An embodiment in which the base material, the ink retaining layer, and the ink permeable layer are all translucent, and the recording material as a whole is translucent.

(2) At least one of the base material, the ink retaining layer, and the ink permeable layer is opaque, and the recording material as a whole is opaque.

In any of the above cases, the ink retaining layer may also have the function of a support.

To explain the invention in more detail using the following two preferred embodiments as representative examples, the base material that can be used as a support in the present invention includes any conventionally known base materials such as transparent and opaque. Examples of suitable transparent substrates include polyester resins, diacetate resins, triacetate resins, acrylic resins, polycarbonate resins, polyvinyl chloride resins, polyimide 1' resins, and cellophane. , films or plates such as celluloid, and glass plates. Preferred examples of the opaque substrate include, for example, general paper, cloth, wood, metal plates, synthetic paper, and the like, as well as the above-mentioned transparent substrates treated to make them opaque by known means. Preferably, such a substrate has a thickness in the range of about lθ to 200 gm.

In the present invention, the ink retaining layer provided on the base material is
It is mainly formed from a hydrophilic material that can accept water-based ink, and is formed as a layer having an ink retention capacity per unit area greater than that of the ink permeable layer described below. Preferred materials include albumin, gelatin, casein, starch, cationic starch, gum arabic, natural resins such as sodium alginate, polyamide, polyacrylamide, polyvinylpyrrolidone, quaternized polyvinylpyrrolidone, polyethyleneimine, and polyvinylpyrrolidone. Lium halide, melamine resin, polyurethane, carboxymethyl cellulose,
Examples include synthetic resins such as polyvinyl alcohol, cation-modified polyvinyl alcohol, polyester, and sodium polyacrylate, and one or more of these materials may be used as desired. Furthermore, in order to reinforce the strength of the ink retaining layer and/or improve the adhesion with the base material, S may be added as necessary.
Resins such as BR latex, NRR latex, polyvinyl formal, polymethyl methacrylate, polyvinyl butyral, polyacrylonitrile, polyvinyl chloride, polyvinyl acetate, phenol resin, and alkyd resin may be used in combination. A method for forming such an ink retaining layer is to prepare a coating liquid by dissolving or dispersing the above-mentioned polymers alone or in a mixture in a suitable solvent;
Preferably, the coating liquid is applied onto the substrate by a known method such as a roll coach ink method, a rot bar coach ink method, an air knife coating method, a spray coating method, etc., and then dried as described above. ,Also,
A single ink-retaining layer is formed from the above-mentioned materials by a known method such as a heat stretching method or a T-die method, and the ink-retaining layer is used so as to have the function of a support. The ink retaining layer may be formed on the base material by laminating the sheet onto the base material, hot melt coating the polymer material, or the like.

The thickness of the ink retaining layer formed in this way may be within a range capable of retaining ink, and although it depends on the amount of ink to be recorded, it is not particularly limited as long as it is at least O,lILm. , Practically, a range of 0.5 to 30 g, m is suitable.

The ink permeable layer used in the present invention and which mainly characterizes the present invention is a thin layer made of natural or synthetic resin provided on the ink retaining layer formed as described above, and the ink permeable layer is a thin layer made of natural or synthetic resin provided on the ink retaining layer formed as described above. When a droplet is deposited, the contact area is rapidly expanded (e.g., within a few seconds) to such an extent that the droplet does not overlap excessively with other adjacent droplets, and the droplet penetrates into the ink reservoir. It also has the function of promoting ink reception by the ink retaining layer.

The inventor of the present invention conducted intensive research in order to impart the above-mentioned functions to the ink-retaining layer, and unexpectedly found that the ink-retaining layer has a hydrophilicity of the same level or the same level as the polymer constituting the ink-retaining layer. It has been found that the above function can be easily achieved by forming a thin layer made of a polymer having an inferior ink retention capacity and having an ink retention capacity less than the ink retention capacity per unit area of the ink retention layer. It was truly surprising that such a function could be achieved even with thin films of polymers that, for example, have no or little solubility in water.

) The ink permeable layer having the function as described in 1 above is made of a polymer having hydrophilicity of about 10% or less than that of the polymer material forming the ink retaining layer. u, -
This was achieved by forming a thin layer having a thickness of less than 1.0 m, preferably about 0.1 to 5 ILm, and an ink retention capacity per unit area of less than the ink retention layer. Polymeric materials useful in forming such thin layers include vinyl acetate,
Homopolymers or copolymers made of acrylic acid esters, ethylene, vinyl chloride, and other vinyl monomers, and polymers made of the above-mentioned vinyl monomers and various hydrophilic vinyl monomers, as well as vinylon, polyurethane, cellulose derivatives, polyesters, polyamides, etc. It is preferable to select a polymer having lower hydrophilicity than the ink-retaining layer from among the above-described polymers for forming the ink-retaining layer, alone or in a mixture.

If the selected material is a polymer that is less hydrophilic than the polymer for the ink retention layer, any polymer may be used as long as the ink retention capacity per unit area is less than or equal to the ink retention layer, and the layer thickness The thickness of the ink retaining layer may be larger than that of the ink retaining layer. On the other hand, when selecting a wood-philic polymer having a hydrophilicity comparable to that of the ink-retaining layer, the thickness of the ink-permeable layer to be formed may be equal to or less than the thickness of the ink-retaining layer.

Further, the selected polymer may be a solution in an organic solvent, but it is preferably used in the form of an emulsion in an aqueous medium, an organic solvent, or a fine dispersion in an aqueous medium.

When used as an organic solvent solution, it is preferable to use a relatively dilute solution or a concentration such that the formed layer falls within the range -F.

The method for forming the ink permeable layer using the above materials may be the same as that for forming the ink retaining layer.

The recording material of the present invention having the above-mentioned basic structure has a hydrophilicity of the ink-permeable layer that is comparable to or inferior to that of the ink-retaining layer, and an ink-retaining layer per medium area of the ink-permeable layer. Although the capacity is less than the ink retaining layer, the recording material of the present invention has remarkable ink receptivity and ink fixing property compared to conventional recording materials without such an ink permeable layer. The improvement is amazing. Although the theoretical basis for this is currently unknown, according to the inventor's mere imagination (the present invention is not limited by such mere imagination), the above-mentioned ink permeable layer is not necessarily continuous. There are countless microscopic gaps in the ink-permeable layer that allow water-based ink to penetrate into the ink-retaining layer, rather than a film, and the surface is irregular on a microscopic scale, resulting in small ink droplets adhering to the layer. quickly diffuses on the surface, expanding their contact area,
Therefore, it is considered that the ink absorption and fixing properties of the ink retaining layer are significantly promoted. In addition, since the ink permeable layer of the recording material of the present invention can be formed from a polymer with lower hydrophilicity than the ink retaining layer, even in a high temperature and high humidity atmosphere, for example, once the ink is received, It does not leach onto surfaces and contaminate equipment, operators, or the surrounding area, nor does the surface become sticky under high temperature and high humidity conditions.

Note that the "ink retention capacity per unit area" used above refers to the capacity that increases continuously over a constant surface area (e.g. fern') of the ink retaining layer or ink permeable layer under an atmosphere of constant temperature and humidity. A certain amount of ink is applied, and after a certain period of time, another piece of paper is pressed against the ink-applied surface.The maximum amount of ink that will not be transferred to the pressed paper.

It means the capacity of ki.

For example, in general, the more hydrophilic the resin, the larger the ink retention capacity, and conversely, the less hydrophilic the resin, the lower the ink retention capacity. The ink holding capacity changes in proportion to the layer thickness.

To specifically determine the ink holding capacity, a sheet of a certain thickness is formed from the resin as described above, for example.

Under the conditions of 20° C. and 65% R)l, ink is deposited on the above layer as small droplets of 85 JLm in diameter, for example several hundred to several tens per cm, by an inkjet recording method.
After a minute has elapsed, the ink holding capacity of the above layer can be determined by pressing it against a separate sheet of paper and checking whether or not ink adheres to the pressed paper, and determining the ink holding capacity of each resin. I can do it.

In the present invention, the ink holding capacity of each resin is compared using the method described above, and a resin with a relatively large ink holding capacity is used as an ink permeable layer; The present invention can be achieved by forming each layer using a smaller layer, or by forming an ink retaining layer and an ink permeable layer with different thicknesses when using layers with the same ink retention capacity. The purpose has been achieved.

The above is the basic structure of the present invention. However, in an embodiment in which the recording material of the present invention is translucent, a translucent material is used as the base material, and when forming the ink retaining layer and the ink permeable layer, , it is necessary to ensure that these layers do not impair translucency. However, filling with silica, clay, talc, diatomaceous earth, calcium carbonate, calcium sulfate, barium sulfate, aluminum silicate, synthetic zeolite, alumina, zinc oxide, lithopone, satin white, etc., to the extent that the translucency is not impaired. Agents can also be dispersed in the ink retaining layer and/or the ink permeable layer.

In the present invention, sufficient light transmittance means that the recording material exhibits a linear light transmittance of at least 2%, and preferably a linear light transmittance of 10% or more.

If the linear light transmittance is 2% or more, it is possible to project and observe the recorded image onto a screen using OHP, for example, and in order to clearly observe the details of the recorded image,
It is desirable that the linear light transmittance is 10% or more. - The linear light transmittance 'T (%) here refers to the light incident perpendicularly to the sample, transmitted through the sample, and separated from the sample by at least 8C■. The spectral transmittance of the straight light that passes through the light-receiving side slit located on the extension line of the incident optical path and is received by the detector is measured using, for example, a 323-type Hitachi self-recording spectrophotometer (Hitachi, Ltd. division). , Further, from the measured spectral transmittance, the Y value of the color tristimulus value is determined, and the value is determined from the following equation.

T=Y/Y, X100 (1) T - Linear transmittance Y; Y value of sample Y, Y value of blank rate (install an integrating sphere behind the sample to determine the transmittance including diffused light), opacity (
The white and black backings are placed on the back of the sample and the ratio is determined. ), which evaluates translucency using diffused light.

The problem with devices that use optical technology is the behavior of straight-line light, so when evaluating the light transmittance of the recording material to be used in those devices, it is important to check the straight-line transmittance of the recording material. It is particularly important to seek

For example, when observing a projected image on an OHP, in order to obtain a clear and easy-to-see image with high contrast between recorded and non-recorded areas, it is necessary to make sure that the non-recorded areas in the projected image are bright, that is, the straight line of the recording material. It is required that the light transmittance be at a certain level or higher. 5 in the OHP test chart test. In order to obtain an image suitable for the purpose described in E, the in-line transmittance of the recording material needs to be 2% or more, and in order to obtain a clearer image, it is preferably 10% or more. Preferably, it is 50% or more. Therefore, a recording material suitable for this purpose needs to have an in-line transmittance of 2% or more.

Further, in an embodiment in which the recording material of the present invention is opaque, an opaque material may be used for at least one layer among the base material, the ink retaining layer, and the ink permeable layer.

The method for forming each layer used in this embodiment is -h
This is the same as in the transparency aspect described above.

In this opaque embodiment, when forming the ink retaining layer and the ink permeable layer, it is possible to use a large amount of the filler to the extent that film forming properties are not impaired, thereby further improving excellent ink receptivity and fixing properties. can.

The present invention has been explained above by illustrating typical aspects of the recording material of the present invention, but of course the recording material of the present invention is not limited to these aspects. Also, the ink retaining layer contains a dispersant, fluorescent dye, p
Various known additives such as H regulators, antifoaming agents, e+ lubricants, preservatives, and surfactants can be included.

Note that the recording material of the present invention does not necessarily have to be colorless, and may be a colored recording material.

As explained above and as demonstrated in the Examples below, the recording material of the present invention as described above has significantly improved ink reception and fixation, and for example, in the case of monochrome as well as full color. When recording images, even if recording liquids of different colors adhere to the same cylinder in duplicate within a short period of time, there is no phenomenon of recording liquid flowing out or seeping out, and images with high resolution, clarity, and excellent color development can be obtained. It will be done. Furthermore, when using an optical device such as a slide or OHP to project a recorded image onto a screen, etc. for observation, attached ink droplets are more likely to interfere with other adjacent areas than with conventional recording materials. Since the images are magnified and fixed to the extent that they do not overlap excessively, the transmitted light becomes even more uniform, giving a projected image with excellent uniform density.Furthermore, it is possible to create a positive plate for color printing. The present invention can be suitably applied to applications other than conventional surface image observation, such as color separation plates used in production, or CMF used in color displays such as liquid crystals.

Hereinafter, the method of the present invention will be explained in more detail according to Examples. Note that parts in each sentence are based on weight.

Example 1 A polyethylene terephthalate film (manufactured by Toshi) with a thickness of 100 ILm was used as a translucent base material, and coating liquid A having the following composition was applied onto this film so that the film thickness after drying was 10 =
The ink was coated using a bar coater method and dried at 60°C for 20 minutes to form an ink retaining layer.
Next, the following coating liquid B'' is applied onto the ink retaining layer so that the dry film thickness becomes IILm, and is dried at 60°C for 15 minutes to form an ink permeable layer. A recording material was obtained.

Coating liquid A composition: Water-soluble acrylic resin (Corgam HW-7, Showa Kobunshi Department) 20 parts Polyvinyl alcohol (PVA-420, manufactured by Kuraray) 5 parts Water
7
5 parts Coating liquid B Composition: Tree-friendly urethane resin (Tricoat G, manufactured by Taiho Industries) 10 parts Acetone 90 parts The recording material of the present invention thus obtained was colorless and transparent.

Example 2 A recording material of the present invention was obtained in the same manner as in Example 1 except that art paper was used as the base material.

Example 3 Thickness 1.00. A polyethylene terephthalate film (manufactured by Music University) was used, and coating solution A with the following composition was applied onto this film until the film thickness after drying was 10011. The ink was coated using a bar coater method to form an ink retaining layer and dried at 80° C. for 1 hour. Next, coating liquid B below was applied to the ink holding layer 1- so that the dry film thickness was 3 pm, and dried at 80°C for 20 minutes to form an ink permeable layer. The ink retaining layer and the ink permeable layer were peeled off together to obtain a translucent recording material of the present invention.

Coating liquid composition: Polyvinyl alcohol (PVA 220, manufactured by Kuraray) 5 parts Polyvinylpyrrolidone 5 parts Water
90 parts Coating liquid B composition: Carboxymethyl cellulose (Shichirogen 83. manufactured by Dai-Kogyo Seiyaku) 2 parts water
98 parts Example 4 The same film as used in Example 1 was used as the base material, and coating liquid A having the following composition was applied onto the base material so that the film thickness after drying was 81 L. It was applied using a coater method and dried at 50°C for 20 minutes to form a retention layer. - Apply Coating Solution B below on the ink retaining layer so that the dry film thickness is 2 g, m - Dry at 70°C for 10 minutes! In this way, an ink permeable layer was formed to obtain the non-transparent recording material of the present invention.

Coating liquid composition: Hydroxyethyl cellulose HEC AH-15 (manufactured by Fuji Chemical) 5 parts water
95 parts Coating liquid B composition Niacrylic resin (Guikaratsuku S-1235, manufactured by Daido Kasei Kogyo Co., Ltd.) 5 parts Ethanol
95 copies Comparative Example 1 A comparative recording material was prepared in the same manner as in Example 1, except that no ink permeable layer was formed.

Comparative Example 2 A comparative recording material was produced in the same manner as in Example 1, except that no ink retaining layer was formed.

Comparative Examples 3 and 4 Using coating liquid B, forming an ink retaining layer on a substrate,
Comparative recording materials were prepared in the same manner as in Examples 1 and 3, except that coating liquid A was applied on the ink retaining layer to form an ink permeable layer.

An on-demand inkjet recording head (discharge orifice diameter: 65 mm layer, piezo vibrator) that ejects ink using a piezo vibrator was used on the recording materials of Examples and Comparative Examples in Section F using the following 411 ink. Drive voltage 7
Inkjet recording was performed using a recording device having a voltage of 0 V and a frequency of 3 KHz.

Yellow ink (composition) C, 1, Direct Yellow 86 2 parts N-methyl-
2-pyrrolidone 10 parts diethylene glycol
20 parts polyethylene glycol #200 15 parts water 55
Part magenta ink (composition) C, X, acid red 35 2 parts N-methyl-
2-pyrrolidone 1o part diethylene glycol
20 parts polyethylene glycol #200 15 parts water 55
Part cyan ink (composition) C, 1, Direct Blue 86 2 parts N-methyl-
2-pyrrolidone 10 parts diethylene glycol
20 parts polyethylene glycol #200 15 parts water 55
Part black ink (composition) C, 1, food black 2 2 parts N-methyl-
2-pyrrolidone 10 parts diethylene glycol
20 parts polyethylene glycol #200 15f4
water
The evaluation results of the recording materials of the 55th example and comparative example are shown in the first
Shown in the table. Each evaluation item in Table 1 was measured according to the following method.

(1) The ink holding capacity of the resin used for the ink holding layer and the ink permeable layer is determined by coating the coating liquid on the same base material as in the example using a bar coater method so that the film thickness after drying is 5 gm. A sample obtained by coating the sample and drying it under the same conditions as in the example was evaluated as follows.

The above sample was coated with ink having a diameter of 85mm by the above inkjet recording method under the conditions of 20°C and 65%RH.
In the state of micro droplets of m, 1, 2, and 4 in one place, that is, 1090 per 1 crn'; 0.35
pu/Cgo, 2180 pieces; 0.7ILl/crrf, 4
360 ink droplets were deposited at a density of 1.4 pu/crn', and after 3 minutes, inkjet recording paper (L paper, manufactured by Mitsubishi Paper Industries) was placed on the deposited area at a density of 1 K g/cm
The ink holding capacity was evaluated.

Even when 4 inks are attached at 1 locations, unfixed ink does not adhere to the inkjet recording paper against which it is pressed, i.e., the capacity to hold ink attached at a density of 1.4 g l'/c rn'. Something with o,
0.1 places can hold up to 2 places with 1 force, Δ, 1 place with 1 force, i.e. 0.3
! Items that cannot hold 1zlL/ctn' of ink
And so.

(2) The ink fixation time was measured by leaving the recording material at room temperature after recording and measuring the time taken for the ink to dry and stop adhering to the finger when touching the recorded image with the finger.

(3) Dot density can be measured using Sakura Microdensidometer PD by applying JIS K7505 to printed microdots.
The black dots were measured using M-5 (manufactured by Konishiroku Photo Industry).

(4) OHP suitability was measured as a representative example of optical equipment, and the recorded image was projected onto a screen using OHP.
Judging by visual observation, the non-recorded area is bright, the OD (optical density) of the recorded image is high, and a clear and easy-to-see projection image with high contrast is obtained. O1 The non-recorded area is slightly dark and the recorded image If the OD of the image is rather low and the line with a pitch width of 0.5 mm and a thickness of 0-25 mm cannot be clearly distinguished, Δ, the non-recorded area is quite dark, the OD of the recorded image is quite low, the pitch width is 1 mm, and the thickness is 0. .3
A sample in which the mm line could not be clearly distinguished or a non-recorded area and a recorded image could not be distinguished was rated as "×".

(5) Straight line transmittance was determined by measuring the spectral transmittance using a 323-type Hitachi self-recording spectrophotometer (newly manufactured by Hitachi), keeping the distance from the sample to the light-receiving side at approximately 9 cm, and measuring the spectral transmittance as described above (
1) It was calculated using the formula.

(J-A page margin) 1 si = Shishiyo Example - Yu 3 4 2 011 amount Ink permeable layer Δ Δ ×
×Ink retaining layer 0 @
0 0 engineering 2 ft. JIE 20℃ 65 canter H15 seconds 15 seconds 45 seconds
15 seconds 20℃ 85 tone 15 seconds 15 seconds 45
Seconds 30 seconds” 78% 80%
81% knee high - [0, 91, 21, 01, OQ once once - suitability 0. 0
0-Reference example- 1 person Dan 4 Fuzz" 01 Sodan ink permeable layer -△ o
.

Ink retention layer ■ −Δ
X4y constant] ■ 1st period 20℃ 85 translation H1 minute 30 minutes or more 5 minutes
5 minutes below - above - my seat 1.0 0
．． 9 0.9 1.0p once once once once ooo.

Claims (1)

[Claims] A recording material having an ink retaining layer and an ink permeable layer, wherein the ink retaining capacity per unit area of the ink retaining layer is greater than or equal to the ink retaining capacity per unit area of the ink transmitting layer. .